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1.
J Proteome Res ; 24(2): 639-648, 2025 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-39792796

RESUMEN

BACKGROUND: Peri-implantitis is characterized as a pathological change in the tissues around dental implants. Fourier-transform infrared spectroscopy (FTIR) provides molecular information from optical phenomena observed by the vibration of molecules, which is used in biological studies to characterize changes and serves as a form of diagnosis. AIMS: this case-control study evaluated the peri-implant disease by using FTIR spectroscopy with attenuated total reflectance in the fingerprint region. METHODS: 38 saliva samples were evaluated, 17 from the control group and 21 from the peri-implantitis group. Clinical data such as plaque index (PI), gingival index, probing depth (PS), and attachment level were assessed. RESULTS: The results of clinical parameters showed a statistical difference between the two groups regarding an excess of the PI. In the FTIR-ATR analysis, the main components revealed vibrational modes of fatty acids, histidine, lipid esters, nucleic acids, and tryptophan, with the main molecules contributing to spectral discrimination. The five-component partial least-squares discriminant analysis classification model had an accuracy of 81%, showing differences between healthy and diseased implants. CONCLUSION: the FTIR spectroscopy provides important molecular characteristics of the samples and the results in association with clinical data show the effectiveness of using this tool for diagnosing the disease.


Asunto(s)
Periimplantitis , Saliva , Humanos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Periimplantitis/diagnóstico , Periimplantitis/patología , Saliva/química , Estudios de Casos y Controles , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Índice de Placa Dental , Índice Periodontal , Implantes Dentales , Análisis Discriminante
2.
J Nanobiotechnology ; 23(1): 51, 2025 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-39875954

RESUMEN

Studies have shown that the prognosis of dental implant treatment in patients with diabetes is not as good as that in the non-diabetes population. The nerve plays a crucial role in bone metabolism, but the role and the mechanism of peripheral nerves in regulating peri-implant osteogenesis under Type 2 diabetes mellitus (T2DM) situation remains unclear. In this study, it was shown that high glucose-stimulated Schwann cells (SCs) inhibited peri-implant osteogenesis via their exosomes. SCs-derived exosomes were analyzed for their miRNA cargo, identifying miR-15b-5p as significantly downregulated in high glucose conditions. T2DM rats and patients exhibited decreased miR-15b-5p expression, correlating with impaired bone microarchitecture. Luciferase assays and Western blotting confirmed TXNIP as a direct miR-15b-5p target, implicating its involvement in ROS signaling and inflammation-related osteogenesis suppression. Furthermore, normal SCs exosomes improved bone parameters around dental implants in T2DM rats. These findings underscore the therapeutic potential of miR-15b-5p and normal SCs exosomes in mitigating poor peri-implant bone regeneration of T2DM patients, offering insights into the molecular mechanisms of peripheral nerves governing bone regeneration in diabetic conditions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Exosomas , MicroARNs , Osteogénesis , Células de Schwann , Transducción de Señal , Exosomas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Animales , Células de Schwann/metabolismo , Ratas , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Masculino , Ratas Sprague-Dawley , Nervios Periféricos/metabolismo , Diabetes Mellitus Experimental/metabolismo , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Glucosa/metabolismo , Implantes Dentales , Proteínas de Ciclo Celular
3.
Med Sci Monit ; 31: e947191, 2025 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-39895039

RESUMEN

BACKGROUND This computer-aided design and computer-aided manufacturing (CAD/CAM) study aimed to evaluate the effects of thermocycling on deep margin elevation relocation of subgingival cavity outlines in 80 molar teeth using advanced lithium disilicate ceramic. MATERIAL AND METHODS Eighty mandibular molar teeth were prepared for deep margin elevation below the cementoenamel junction. The following types of restorations were subsequently applied to each group: glass ionomer filling, bulk-fill flowable resin composite, bioactive resin composite, and nanohybrid resin composite. Full-coverage crowns with standardized preparation and a shoulder finish line were prepared to receive CAD/CAM-milled advanced lithium disilicate crowns. Samples were examined at 6 equidistant points via digital microscope on each proximal surface at the restoration-tooth and crown-restoration interfaces before and after thermocycling for 15 000 cycles. Data were analyzed using one-way analysis of variance, at a level of significance of 0.05. RESULTS The vertical marginal gap was significantly higher after aging and was the highest for glass ionomer filling, 9.091 (±1.147) and 9.936 (±6.376) µm, followed by nanohybrid resin composite, 3.59 (±1.03) and 3.87 (±0.97) µm, bioactive resin composite, 3.17 (±0.81) and 2.59 (±0.21) µm, and bulk-fill flowable resin composite, 1.89 (±0.60) and 2.42 (±0.64) µm, at the cervical and apical interfaces, respectively. CONCLUSIONS Thermocycling significantly changed the marginal adaptation of all restorative materials. Highest values for marginal adaptation were recorded in the glass ionomer filling group, followed by nanohybrid composite and bioactive resin groups, whereas lowest values were recorded among the bulk-fill flowable resin composite group at cervical and apical interfaces.


Asunto(s)
Resinas Compuestas , Diseño Asistido por Computadora , Coronas , Adaptación Marginal Dental , Porcelana Dental , Humanos , Diente Molar , Cerámica , Restauración Dental Permanente/métodos , Materiales Dentales , Diseño de Prótesis Dental/métodos , Ensayo de Materiales/métodos
4.
J Mater Sci Mater Med ; 36(1): 12, 2025 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-39812714

RESUMEN

Although implants have undergone a remarkable development over the past decades, modern implants still show complications that make the improvement of materials necessary. The presented study investigates the load-bearing capacity of an experimental dental implant made of a niobium alloy (Nb1Zr) compared to identical implants made of Ti6Al4V using chewing simulation for artificial aging. Eight implants each with an experimental design were manufactured from Nb1Zr and Ti6Al4V. A standardized abutment made of Ti6Al4V was fabricated for each implant and screwed into the implant with a screw made of the same material. A shape-identical crown for an upper first molar was fabricated for all implants using the CAD/CAM technique. All specimens were artificially aged using chewing simulation for 1 × 106 cycles and thermocycling between 5 °C and 55 °C for 4 × 103 cycles. After that, all specimens were loaded until failure. This was followed by a 3D analysis of the deformation of the samples. 100% of the samples survived the artificial aging. The Nb1Zr samples failed at 2595 ± 1069 N. In the Ti6Al4V group, failure occurred at 2958 ± 1058 N. The first deformations occurred in both groups from a load of at least 1114 N. The 3D analysis revealed deformations of 0.08 mm in the implant shoulder area of the Nb1Zr implants and of 0.04 mm in the Ti6Al4V implants. This difference was significant (p = 0.016). The investigated Nb1Zr alloy appears to be suitable for implants. The measured load-bearing capacity is significantly higher than the expected intraoral masticatory forces.


Asunto(s)
Aleaciones , Implantes Dentales , Ensayo de Materiales , Niobio , Titanio , Soporte de Peso , Niobio/química , Aleaciones/química , Titanio/química , Estrés Mecánico , Humanos , Diseño Asistido por Computadora , Implantes Experimentales , Aleaciones Dentales/química , Análisis del Estrés Dental , Diseño de Prótesis Dental , Masticación , Propiedades de Superficie , Fracaso de la Restauración Dental
5.
Lasers Med Sci ; 40(1): 39, 2025 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-39849248

RESUMEN

The aesthetic understanding has found its place in dental clinics and prosthetic dental treatment. Determining the appropriate prosthetic tooth color between the clinician, patient and technician is a difficult process due to metamerism. Metamerism, known as the different perception of the color of an object under different light sources, is caused by the lighting differences between the laboratory and the dental clinic. The traditional trial-error color determination method, coupled with the high cost of instrumental color value determination, has prompted the need for alternative technologies. The integration of AI technologies into dental practices aims to minimize errors in tooth shade assessment, reduce equipment usage, eliminate the impact of clinic lighting on color detection, and decrease costs for patients, dentists, and laboratories. In this study, a machine learning (ML) based approach that can correctly detect tooth shade even under different clinical lights has been developed. A dataset consisting of 580 dental images taken under four different clinical lights and with five repetitions was created using the Vita color shade guide. Experimental studies were performed using the HSV color space, 6 different ML algorithms and color histograms. As a result, 97.93% accuracy rate was achieved by using cross-validation (cv = 5) in the classification of 29 color values ​​independent of clinical lights. It has been shown that the tooth colors can be determined with high accuracy using ML algorithms and metamerism can be prevented.


Asunto(s)
Aprendizaje Automático , Diente , Humanos , Iluminación , Color , Coloración de Prótesis/instrumentación , Coloración de Prótesis/métodos , Algoritmos
6.
Lasers Med Sci ; 40(1): 40, 2025 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-39853546

RESUMEN

This systematic review and meta-analysis aimed to compare the effect of photobiomodulation (PBM) therapy on implant stability and crestal bone loss placed in healed sites. The present systematic review and meta-analysis were conducted according to PRISMA (The Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Two investigators carried out the electronic search of Pubmed, Google Scholar, and Ebscohost for published literature from 2012 till March 2024. Handsearch for articles relevant to the topic was also carried out along with references. Only randomized controlled trials were included for systematic review. The assessment quality was done using the revised JBI checklist (Joanna Biggs Institute). After screening and eligibility assessment, Qualitative analysis was envisaged for 15 studies on implant stability and crestal bone loss, followed by quantitative analysis of 8 studies on implant stability and only 2 studies for crestal bone loss. Meta-analysis showed that overall implant stability was significantly higher in the control group (P < 0.00001). Crestal bone loss showed a significant difference after the therapy when observed after six months of implant placement (P = 0.03). Heterogeneity was high with the random effects model for implant stability, while it was acceptable for crestal bone loss. However, more studies with similar parameters concerning implant stability and PBM characteristics are required for further subgroup analysis and to reach conclusive results.


Asunto(s)
Pérdida de Hueso Alveolar , Implantes Dentales , Terapia por Luz de Baja Intensidad , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Terapia por Luz de Baja Intensidad/métodos , Pérdida de Hueso Alveolar/radioterapia , Pérdida de Hueso Alveolar/etiología , Implantación Dental Endoósea/métodos , Resultado del Tratamiento
7.
Clin Oral Investig ; 29(1): 39, 2025 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-39743647

RESUMEN

OBJECTIVES: The study aimed to assess the percent correct shade identification of four intraoral scanners (IOS) and a spectrophotometer, focusing on how reliably each device selects the correct tooth shade compared to a visual observer's selection. The research question addresses how much clinicians can trust the device-selected shade without visual verification. MATERIALS AND METHODS: Sixteen participants with natural, unrestored teeth were included. The teeth evaluated were tooth 21 (left maxillary central incisor), tooth 23 (left maxillary canine), and tooth 26 (first left maxillary molar). Tooth color was measured using four IOS devices and the Vita Easyshade V in three regions: incisal, middle, and cervical. The nearest 3D Master shade selected by each device was compared to the visual observer's selection. The percent exact match, acceptable match (> 1.2, ≤ 2.7 ∆Eab), and mismatch type A (< 2.7, ≤ 5.4 ∆Eab) were calculated. Statistical analysis was performed using a chi-square test with a 95% confidence level. RESULTS: The overall clinical pass rate was highest for Carestream (78.2%), followed by Easyshade (63.5%), Primescan (51.2%), Trios (39.5%), and Medit (31.3%). Carestream also recorded the highest rate of mismatch type A (47.7%). Significant differences between devices were observed for all categories (p < 0.05). CONCLUSIONS: Carestream demonstrated the highest overall clinical pass rate, while Medit exhibited the lowest. The study highlights the variability between devices in shade matching performance. CLINICAL RELEVANCE: This study highlights the importance of considering device performance when relying on IOS or spectrophotometers for shade selection without visual assessment, as the reliability can vary significantly across devices.


Asunto(s)
Espectrofotometría , Humanos , Espectrofotometría/instrumentación , Femenino , Masculino , Coloración de Prótesis/instrumentación , Adulto , Color
8.
Clin Oral Investig ; 29(2): 96, 2025 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-39875663

RESUMEN

OBJECTIVE: To evaluate short, mid and long-term clinical outcomes and patients' satisfaction of minimally invasive full-mouth rehabilitation using different materials and techniques for patients with moderate to severe tooth wear. Furthermore, materials were analyzed to identify their influences on clinical results. MATERIALS AND METHODS: Search was conducted in PubMed, Cochrane Central Register of Controlled Trial, Embase, Web of science and Scopus until December 19, 2024. Randomized clinical trials (RCT), cohort studies and case series with at least mean period of 3 years were included. The revised Cochrane risk of bias tool, Newcastle-Ottawa scale and Joanna Briggs Institute Critical Appraisal were used to evaluate the quality of RCT, cohort studies and case series. Meta-analysis and Poisson regression were conducted. RESULTS: Ten studies in this review included three case series, six cohort studies and one RCT with three low, six moderate risks and one some concerns. Annual failure rates (AFRs) and annual complication rates (ACRs) of direct composite restorations were 0-6.2% and 1.0%-4.2%, respectively. AFRs of indirect restorations were 0%-0.5%. Overall ACRs of indirect restorations fabricated by traditional indirect resin composites, polymer-infiltrated ceramic-network, resin nanoceramics and ceramics were at 1.6%-15.1%, 0.7%-4.8%, 0.5%-5.0% and 0.2%-1.1%, respectively. The estimated AFRs of direct composites, resin nanoceramics and ceramics were 0.64%, 0.13% and 0.04% respectively. Significantly lowest AFRs of ceramic was found after mid-term follow-up with incidence rate ratios of direct composites, resin nanoceramics and ceramics being 1: 0.68 (P = 0.60): 0.001 (P < 0.05). The estimated ACRs of the three materials were 2.16%, 2.14% and 0.62%. Overall AFRs of restorations using different techniques were 0%-0.5%. Overall ACRs of direct and indirect techniques were 1.1%-2.2% and 0.2%-4.8%, respectively. Overall ACRs of hybrid technique were 0.5% to 15.1%. Restoration fracture was the most predominant complication regardless of materials. High appreciation was expressed by patient reported outcomes measures. CONCLUSIONS: Minimally invasive full-mouth rehabilitation for patients with moderate to severe tooth wear presented good clinical performance apart from traditional indirect resin composite used in posterior teeth. CLINICAL RELEVANCE: Minimally invasive full-mouth rehabilitation should be strongly advocated for the patients with moderately and severely worn dentition.


Asunto(s)
Restauración Dental Permanente , Rehabilitación Bucal , Desgaste de los Dientes , Humanos , Desgaste de los Dientes/terapia , Desgaste de los Dientes/rehabilitación , Restauración Dental Permanente/métodos , Rehabilitación Bucal/métodos , Materiales Dentales/química , Resinas Compuestas , Fracaso de la Restauración Dental , Satisfacción del Paciente
9.
Clin Oral Investig ; 29(1): 51, 2025 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-39779583

RESUMEN

OBJECTIVES: To compare the impact of intaglio surface treatments - airborne particle abrasion and hydrofluoric acid (HF) etching - of feldspar ceramic (FEL) crowns on the fracture load (FL) and to investigate the effects of abutment materials and artificial aging. The aim was to assess whether etching could be replaced by an alternative surface roughening method. MATERIALS AND METHODS: FEL crowns had their intaglio surfaces either abraded (25 µm Al2O3, 0.1 MPa), etched (HF, 60 s), or untreated and then bonded to CoCrMo- and polymer-abutments. FL was measured for non-aged and aged (1.2 million mastication cycles) specimens. Data were analyzed using, Weibull modulus, two-/one-way ANOVA with Tukey HSD-post-hoc-test, t-tests, and TOST equivalence (p < 0.05). RESULTS: For crowns bonded to CoCrMo abutments, aging affected the FL and Weibull modulus, but pretreatment methods did not. For initial specimens, airborne abraded and etched crowns were equivalent within a 400N bound, however, for aged specimens, equivalence was inconclusive. For crowns bonded to polymer-abutments, pretreatment and aging influenced the FL. Etching decreased the initial FL by over 420N compared to airborne abraded and untreated specimens. After aging, untreated crowns' FL decreased by 528N, while airborne abraded and etched specimens showed no aging effect. CONCLUSIONS: Airborne particle abrasion of FEL crowns' intaglio surfaces did not negatively impact FL and was comparable to etched crowns. Conclusions regarding pretreatment methods and aging differed between CoCrMo- and polymer-abutments. CLINICAL RELEVANCE: Airborne particle abrasion may be an alternative procedure for the intaglio surface treatment of FEL crowns prior bonding.


Asunto(s)
Silicatos de Aluminio , Coronas , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Ensayo de Materiales , Compuestos de Potasio , Propiedades de Superficie , Compuestos de Potasio/química , Silicatos de Aluminio/química , Cerámica/química , Pilares Dentales , Grabado Ácido Dental , Grabado Dental/métodos , Ácido Fluorhídrico/química , Porcelana Dental/química
10.
BMC Oral Health ; 25(1): 143, 2025 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-39871197

RESUMEN

BACKGROUND: In the maxillary anterior region, differences in bone density along the drilling path can impact the accuracy of implant placement despite the use of a surgical guide. Hence, the aim of this in vitro study was to investigate the accuracy of implant placement using the over-preparation technique in different drilling environments in the maxillary anterior region. METHODS: Three experimental models (a, b, and c) were designed and fabricated to simulate the following drilling environments (n = 60 each): unhealed bone, less dense bone, and dense bone after tooth extraction. The models were subjected to implant cavity preparation and placement using the over-preparation technique (group OPT) and conventional surgical guide technique (group CGT). Differences between the actual positions and the planned positions of the implants were calculated. RESULTS: The deviations of the implants in the group OPT in Model a and Model b were significantly smaller than those in the group CGT (P < 0.05). Among the group OPT, Model c presented with the smallest deviation, followed by Model b and Model a (P < 0.05), and the CGT group showed the same trend. CONCLUSIONS: In the maxillary anterior region, differences in bone density along the drilling path can adversely affect the accuracy of implant placement. These discrepancies can be significantly minimized using the over-preparation technique.


Asunto(s)
Implantación Dental Endoósea , Maxilar , Maxilar/cirugía , Humanos , Técnicas In Vitro , Implantación Dental Endoósea/métodos , Densidad Ósea , Implantes Dentales
11.
BMC Oral Health ; 25(1): 58, 2025 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-39799312

RESUMEN

BACKGROUND: Increasing demand for durable and aesthetically pleasing dental restorations, including laminates, inlays, onlays, and crowns, has led to advancements in all-ceramic systems, particularly with the development of advanced lithium disilicate materials. However, limited data on the fit accuracy and fracture resistance of these materials restricts their wider application in clinical restorative practices. AIM OF THE STUDY: This in vitro study aims to compare the marginal and internal fit, assess the fracture resistance, and evaluate the failure modes of crowns fabricated from advanced and conventional lithium disilicate materials. MATERIALS AND METHODS: Thirty two (n = 32) crowns were fabricated and categorized into two groups based on the material used: Group (CT), where crowns were milled from CEREC Tessera (n = 16), and Group (EM), where crowns were milled from IPS e.max CAD (n = 16) using a CAD/CAM system. The marginal and internal fit were assessed digitally via a triple scan protocol. All samples were subjected to a fracture resistance test with a universal testing machine, followed by an analysis of failure modes under a stereomicroscope. RESULTS: In the evaluation of marginal, internal and total gaps, CEREC Tessera (CT) showed slightly better fit with lower gap values compared to e.max CAD (EM). However, an independent samples t-test indicated no statistically significant differences between the two groups (p = 0.141, p = 0.471). For fracture resistance (N), the CT group demonstrated higher values than the EM group; however, the independent samples t-test indicated no statistically significant difference (p = 0.053). Additionally, the Chi-squared test with Monte Carlo correction revealed no statistically significant differences in the modes of fracture between the two groups (p = 0.484). CONCLUSION: Considering the limitations of this study, advanced lithium disilicate crowns demonstrated better results in terms of marginal fit, internal adaptation, and fracture resistance compared to traditional lithium disilicate crowns; however, the differences were not statistically significant. Both materials exhibited comparable fracture patterns.


Asunto(s)
Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Porcelana Dental/química , Técnicas In Vitro , Humanos , Ensayo de Materiales , Análisis del Estrés Dental , Adaptación Marginal Dental , Cerámica/química
12.
BMC Oral Health ; 25(1): 176, 2025 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-39893449

RESUMEN

BACKGROUND: Pulpal extension depth (PED) is critical for endocrowns restored teeth stability and longevity. There is a conflicting result regarding the minimum PED needed for the success of endocrowns. The aim of the current study was to compare Fracture resistance, failure mode, and restorability of CAD-CAM zirconia endocrowns with different pulpal extension depths bonded to maxillary molars. MATERIALS AND METHODS: Forty maxillary 1st molars were selected, decoronated, and randomly divided into 4 main groups (n = 10) according to the PED measured from the pulpal floor to the occlusal end of the wall height into; group D2, PED was 2 mm, group D3, PED was 3 mm, group D4, PED was 4 mm, group D5 PED was 5 mm. Teeth were prepared and secured in resin dies with pseudo periodontal ligament. Specimens from all groups were individually scanned using an intra oral digital scanner. Monolithic zirconia endocrowns were constructed and bonded to their corresponding. Following thermal cycling, each specimen was axially loaded in a universal testing machine at a 0.5 mm/min crosshead speed. Failure modes were inspected, and restorability of specimens was recorded. Data was collected, tabulated, and statistically analyzed. RESULTS: Descriptive statistics displayed higher mean value of the D2 group (3657 1673.8 N) followed by the D3 group (3009.3 853.5 N), then the D4 group (2087.3 413.9 N) and finally the D5 group (1972.7 ±330.4 N). At a 95% confidence level, one-way analysis of variance (ANOVA) revealed significant differences between tested groups. (P = 0.014). Regarding failure mode, D2 recorded 100% restorable failures, followed by D3 (90%) and D4 (60%), while the least was D5 (50%). CONCLUSIONS: Endocrowns with 2 mm PED recorded the highest fracture resistance and the highest restorable failure modes. Endocrowns with 5 mm PED recorded the lowest fracture resistance and the lowest restorable failure modes. Tall walls should be shortened during the preparation of endocrowns in maxillary molars.


Asunto(s)
Diseño Asistido por Computadora , Fracaso de la Restauración Dental , Maxilar , Diente Molar , Circonio , Circonio/química , Humanos , Análisis del Estrés Dental , Técnicas In Vitro , Pulpa Dental , Ensayo de Materiales , Coronas , Fracturas de los Dientes/prevención & control , Recubrimiento Dental Adhesivo/métodos , Diseño de Prótesis Dental
13.
BMC Oral Health ; 25(1): 186, 2025 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-39905379

RESUMEN

BACKGROUND: The effect of immediate dentin sealing (IDS) or delayed dentin sealing (DDS) on bond strength of different ceramic occlusal veneer restorations, was not examined yet, but the digital quantification of surface area of preparations helped in the calculation of the actual bond strength of these restorations, besides that, dentin sealing could influence the fracture resistance values of different ceramic occlusal veneer restorations. This study aimed to examine the effect of different dentin sealing strategies and different restorative materials on the debonding forces, bond strength and fracture resistance of occlusal veneer restorations. MATERIALS AND METHODS: Human mandibular molars (N = 64/test) were prepared for occlusal veneer restorations fabricated from Lithium disilicate ceramic (LS) (control group), Zirconia-reinforced lithium Silicate ceramic (ZLS), High translucent zirconia ceramic (HZ), and Resin nano ceramic (LU) (n = 16). Each material was subdivided according to IDS or DDS application, (n = 8). Bond strength testing and fracture resistance values were measured using universal testing machine. Two-way ANOVA was performed to investigate the effects of the two variables, dentin sealing and material selection, and their interaction (α = 0.05), followed by One-way ANOVA and post hoc or Student t-test for further determination of significance. RESULTS: For debonding forces and bond strength testing there were significant differences regarding different materials and dentin sealing strategies, while for fracture resistance, the material selection had a significant effect on it with no significant effects of dentin sealing strategies. The interaction between materials and dentin sealing showed no significant differences concerning all tests. For debonding forces and bond strength there was a higher result related to IDS application than DDS (p < 0.001*), and there was a significant effect of material selection on them (LS > ZLS > HZ > LU), (p = 0.001*). Regarding the fracture resistance there was significant increase of all studied materials than LU (p = 0.002*). CONCLUSION: Immediate dentin sealing increased the required debonding forces of occlusal veneers made of different materials and their bond strength without significant effect on their fracture resistance, however this improvement was found to be material dependant. All the used materials can withstand lateral and occlusal forces higher than the values recommended for restoring posterior teeth.


Asunto(s)
Cerámica , Recubrimiento Dental Adhesivo , Análisis del Estrés Dental , Coronas con Frente Estético , Circonio , Humanos , Recubrimiento Dental Adhesivo/métodos , Cerámica/química , Circonio/química , Dentina , Porcelana Dental/química , Ensayo de Materiales , Fracaso de la Restauración Dental , Recubrimientos Dentinarios/química , Diente Molar
14.
BMC Oral Health ; 25(1): 142, 2025 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-39871214

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the effect of different preparation depths (0, 2 and 4 mm) of different restoration designs (classic endocrown design versus overlay design) on marginal adaptation of restorations fabricated of two different restorative materials (lithium disilicate and PEEK). MATERIALS AND METHODS: Sixty mandibular natural molars were collected as abutments for the restorations of this study, and grouped in three main groups of different cavity depths (0, 2 and 4). Each group was divided into two subgroups according to material of fabrication to (L) for lithium disilicate (IPS emax CAD, Ivoclar vivadent, Switzarland) and (P) for PEEK (Bio-hpp, Bredent, Germany). CAD/CAM milling technology was used for fabrication of restorations. After cementation of restorations over abutments, hydrothermal aging was performed, and then marginal adaptation was evaluated via micro CT technology. RESULTS: Regarding cavity depths, there was a significant difference between different groups (p < 0.001). The highest value was found in samples with 4 mm extension (84.35 ± 18.16), followed by samples with 2 mm extension (66.52 ± 21.86), while the lowest value was found in samples without pulpal extension (59.41 ± 22.16). Post hoc pairwise comparisons showed samples with 4 mm extension to have a significantly higher value than samples without extension (p < 0.001). Regarding materials of fabrication, PEEK (85.32 ± 12.37) had a significantly higher value than Emax (54.86 ± 20.86) (p < 0.001). CONCLUSIONS: Increasing intrapulpal cavity depths increases vertical marginal gap of lithium disilicate or PEEK restorations. Endocrowns fabricated of lithium disilicate show less marginal discrepancies than that of endocrowns fabricated of PEEK.


Asunto(s)
Diseño Asistido por Computadora , Adaptación Marginal Dental , Diente Molar , Polietilenglicoles , Microtomografía por Rayos X , Humanos , Microtomografía por Rayos X/métodos , Técnicas In Vitro , Diente Molar/diagnóstico por imagen , Polímeros , Porcelana Dental/química , Benzofenonas , Cetonas/química , Diseño de Prótesis Dental , Coronas , Preparación de la Cavidad Dental/métodos , Materiales Dentales/química , Restauración Dental Permanente/métodos
15.
BMC Oral Health ; 25(1): 92, 2025 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-39825302

RESUMEN

BACKGROUND: The continuous development in digital prosthodontics allowed the customization of attachments and retentive inserts which offers an easy and cheap solution for regular maintenance of locator overdentures during daily practice. The present study compared the change in retention values of the fully digitally manufactured custom-made locator attachment retentive insert with the ready-made ones after insertion, removal, and masticatory cycles. METHODS: A complete denture was constructed over a mandibular edentulous epoxy model. Two implants were inserted into the model between the laterals and canines following the prosthetically driven implant protocol. Locator retentive attachment inserts were digitally designed using free-form modeling software and milled from PEEK (Poly Ether Ether Ketone). After the pick-up of the ready- and custom-made retentive inserts, an insertion, removal, and masticatory cycles test simulating 1 year of patient usage was performed. The change in retention values was recorded at baseline, 6 months, and after one year of simulated clinical use. An independent sample t-test was used to compare the data between the two studied groups. RESULTS: There were statistically significant differences in retention values between the custom-made and ready-made locator inserts at baseline and after 6 months. (p = 0.001*). On the other hand, there was no significant difference in retention after 1 year of simulated use. (p = 0.083, NS) CONCLUSIONS: The custom-made milled locator retentive attachment insert can be used as an alternative to the ready-made one due to their comparable retention values after 1 year of simulated use.


Asunto(s)
Diseño Asistido por Computadora , Prótesis Dental de Soporte Implantado , Diseño de Dentadura , Retención de Dentadura , Prótesis de Recubrimiento , Retención de Dentadura/instrumentación , Humanos , Dentadura Completa Inferior , Masticación/fisiología , Mandíbula , Estudios de Seguimiento
16.
BMC Oral Health ; 25(1): 31, 2025 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-39773215

RESUMEN

OBJECTIVES: To compare the stress distribution and crack propagation in cracked mandibular first molar restored with onlay, overlay, and two types of occlusal veneers using two different CAD/CAM materials by Finite Element Analysis (FEA). MATERIALS AND METHODS: A mandibular first molar was digitized using a micro CT scanning system in 2023. Three-dimensional dynamic scan data were transformed, and a 3D model of a cracked tooth was generated. Finite element models of four different models (onlay, overlay, and two types of occlusal veneer restored teeth) were designed. Two different CAD/CAM materials, including Lava Ultimate (LU) and IPS e.max CAD (EMX), were specified for both models. Each model was subjected to three different force loads on the occlusal surfaces. Stress distribution patterns and the maximum von Mises (VM) stresses were calculated and compared. RESULTS: Compared to the base model, all restorations showed that high-stress concentration moved from the lower margin of the crack area towards the top of the crack area. The EMX-restored onlay, overlay, and occlusal veneer 2 had the lower stress in the cracked area and the lower average von Mises stress levels at the lower margin along the cracked line, especially under the 225N lateral force (P < 0.05). The occlusal veneer 1 filled with resin had a poorer stress distribution and higher stress concentration of stress at the remaining crack than the occlusal veneer 2 without resin filled inside. CONCLUSIONS: The EMX restorations with onlay, overlay, and occlusal veneer 2 showed lower stress concentration at the lower margin of crack surface compared to the LU-restored models. The occlusal veneer with internal resin filler exhibited higher stress on the end of the lower margin of the crack surface. CLINICAL RELEVANCE: Our results suggest that onlay, overlay ceramic restorations and occlusal veneer (without resin filling inside) may be a favorable method to prevent further crack propagation. TRIAL REGISTRATION: A protocol was specified and registered with the Chinese Clinical Trial Registry (ChiCTR) on 2022-04-12 (registration number: ChiCTR2200058630).


Asunto(s)
Análisis del Estrés Dental , Coronas con Frente Estético , Análisis de Elementos Finitos , Humanos , Análisis del Estrés Dental/métodos , Diente Molar , Diseño Asistido por Computadora , Síndrome de Diente Fisurado/fisiopatología , Materiales Dentales/química , Microtomografía por Rayos X , Incrustaciones , Estrés Mecánico , Restauración Dental Permanente/métodos , Diseño de Prótesis Dental , Porcelana Dental/química
17.
BMC Oral Health ; 25(1): 40, 2025 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-39773219

RESUMEN

PURPOSE: The current study aimed to compare modified Polyether-ether-ketone's fracture resistance and failure mode versus lithium disilicate glass-ceramic endocrowns. MATERIALS AND METHODS: A total of 16 butt-joint endocrown specimens on mandibular second molar teeth were fabricated and divided into two equivalent groups; Pressable modified Polyether-ether-ketone (PEEK) (BioHPP®) and Pressable lithium disilicate glass ceramic (IPS e.max® Press). A computer-aided design/computer-aided manufacturing system was used to digitally create and milled wax patterns. Final restorations were cemented each to its corresponding prepared tooth. Thermomechanical cycling loading representing one year of clinical service was done in a chewing simulator. Fracture resistance was evaluated utilizing a universal testing machine. The failure mode was evaluated by inspecting fractured surfaces using a Stereomicroscope and further examined by a Scanning Electron Microscope (SEM) amongst both groups. RESULTS: A statistically significant variation in fracture resistance was recorded with a mean load of (2762.96 ± 216.15 N) for modified PEEK and (2175.91 ± 267.72 N) for lithium disilicate glass-ceramic endocrowns. CONCLUSION: Modified PEEK endocrowns have higher fracture resistance than lithium disilicate glass-ceramic endocrowns. Moreover, the likeliness of catastrophic fracture in molars receiving endodontic treatment restored by modified PEEK is less than teeth restored with lithium disilicate glass ceramics.


Asunto(s)
Benzofenonas , Cerámica , Diseño Asistido por Computadora , Porcelana Dental , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Cetonas , Ensayo de Materiales , Polietilenglicoles , Polímeros , Cetonas/química , Porcelana Dental/química , Humanos , Polietilenglicoles/química , Cerámica/química , Microscopía Electrónica de Rastreo , Coronas , Diente Molar
18.
BMC Oral Health ; 25(1): 131, 2025 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-39856698

RESUMEN

PURPOSE: The aim of this study was to compare the wear and fracture resistance of single crowns produced from newly developed 3D printer resins used to produce permanent crowns and currently used composite CAD/CAM discs, after being thermomechanically aged in a chewing simulator. MATERIALS AND METHODS: A total of 112 stainless steel die models simulating mandibular left first molars were produced, 8 for each group. Single crowns were produced from 3 different discs (Grandio Voco [GR], breCAM HIPC [HC], and Shofu HC [SF]) by CAD/CAM milling method and manufactured from from 4 different permanent composite resins (Nexdent C&B MFH [ND], Permanent Bridge Saremco [PB], VarseoSmile Crownplus [VSC], and Senertek P-Crown [PC]) using the 3D printing method. Stereomicroscopy, scanning electron microscope (SEM) and Finite Element Method (FEM) analysis was performed. Data were analyzed using ANOVA, paired-t tests and Tukey's HSD test (alpha = 0.05). RESULTS: As a result of thermomechanical aging, significant difference was found between the groups in wear and fracture resistance (P < .05). The highest wear resistance was found in the VSC group, and the lowest wear resistance in the PC group. As a result of the compression test, the highest fracture resistance was noted in the GR group and the lowest in the PC group. FEM analysis performed to validate fracture experiments showed an 87% similarity to the in-vitro data. CONCLUSIONS: The crowns in all groups produced by CAD/CAM milling and 3D printing provided acceptable in vitro wear and fracture resistance for clinical application. The wear and fracture resistance of resin-based materials should be supported by clinical studies.


Asunto(s)
Resinas Compuestas , Diseño Asistido por Computadora , Coronas , Análisis de Elementos Finitos , Impresión Tridimensional , Resinas Compuestas/química , Ensayo de Materiales , Humanos , Microscopía Electrónica de Rastreo , Diseño de Prótesis Dental , Análisis del Estrés Dental , Fracaso de la Restauración Dental
19.
BMC Oral Health ; 25(1): 208, 2025 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-39923032

RESUMEN

BACKGROUND: The advent of 3D-printing technology, which is capable of on-demand fabrication, has ushered in a new era for fixed implant prosthodontics. Over the past decade, immediately loaded 3D-printed titanium implants have demonstrated predictable clinical outcomes in human jaws, highlighting their superior osseointegration strength, which is attributed to their increased surface roughness. However, the biomechanical mechanisms underlying this enhanced osseointegration strength remain elusive, thereby impeding the standardization and broader clinical application of 3D-printed titanium implants. METHODS: Experimental 3D-printed titanium implants were fabricated via selective laser melting (SLM), and conventional sandblasted and acid-etched titanium implants (CNC-SLA) served as the control group. Implant surfaces were characterized with scanning electron microscopy, surface profilometry, energy-dispersive X-ray spectroscopy, and a contact angle meter. Implants (n = 10) were surgically inserted into the femoral condyle of New Zealand rabbits. At weeks 1, 2, and 8, micro-CT and undecalcified histological sections were used to assess histological osseointegration (n = 6), whereas removal torque analysis was performed to evaluate osseointegration strength (n = 4). At week 8, microscale finite element analysis of different bone-implant interfaces was conducted to predict the peri-implant bone strain under multidirectional implant loading. RESULTS: The surface roughness of the SLM implants was significantly greater than that of the CNC-SLA implants. Histological osseointegration assessments revealed equal levels of SLM and CNC-SLA implants at weeks 1, 2, and 8. Notably, after week 2, bone interlocking phenomenon appeared on the SLM implants. The removal torque for the SLM implants at week 2 were significantly greater (P < 0.05) than that for the CNC-SLA implants at the same time point and was comparable to the CNC-SLA implants at week 8 (P = 0.775). The removal torque for the SLM implants at week 8 was further increased. Microscale finite element analysis revealed that the rough surface of the SLM implants dispersed harmful strains at the bone-implant interface into the surrounding bone, thereby mitigating the risk of damage to the bone-implant interface. CONCLUSIONS: The rough surface of 3D-printed titanium implants fosters microscale bone interlocking and alleviates peri-implant bone strain concentration, which is a promising biomechanical basis for osseointegration strength.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental , Análisis de Elementos Finitos , Oseointegración , Impresión Tridimensional , Propiedades de Superficie , Titanio , Titanio/química , Animales , Conejos , Microscopía Electrónica de Rastreo , Microtomografía por Rayos X , Torque
20.
BMC Oral Health ; 25(1): 61, 2025 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-39799344

RESUMEN

BACKGROUND: The stability of soft and hard tissues surrounding the implant is not only a matter of aesthetics, but also affects the long-term stability of the implant. The present study was to explore the influence of buccal mucosa width/height (W/H) ratio, emergence profile and buccal bone width on peri-implant soft and hard tissue changes in the posterior region. METHODS: Fifty-eight posterior implant restoration cases were recruited in this study. Evaluations were performed at the time of restoration placement (T0), and 1 year later (T1). Buccal mucosa width (BMW), buccal bone width (BBW), implant buccal inclination angle, and emergence angle were evaluated. The variables that may affect buccal mucosa recession (MR) as well as vertical bone loss (VBL) were analyzed. RESULTS: The BMW at baseline was 2.93 ± 1.01 mm. The BBW at baseline was 1.50 ± 0.82 mm. The buccal mucosa W/H ratio at 1 year (1.23 ± 0.38) was significantly lower than that at baseline (1.42 ± 0.45). Buccal MR was - 0.22 ± 0.47 mm while VBL was 0.81 ± 0.80 mm. The correlation between MR and initial BMW (r=-0.381), initial W/H ratio (r=-0.422), BBW (r=-0.290) was statistically significant. The correlation between VBL and initial BMW (r=-0.421), initial W/H ratio (r=-0.305), implant buccal inclination angle (r = 0.507), BBW (r=-0.556) was statistically significant. CONCLUSIONS: Within the scope of this study, implant sites in the posterior region presenting a thin BMW, a thin BBW, and a small W/H ratio are more prone to exhibit buccal mucosa recession and vertical bone loss.


Asunto(s)
Mucosa Bucal , Humanos , Estudios Prospectivos , Mucosa Bucal/anatomía & histología , Mucosa Bucal/patología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Implantes Dentales , Pérdida de Hueso Alveolar/patología , Proceso Alveolar/patología , Proceso Alveolar/anatomía & histología , Recesión Gingival/patología , Implantación Dental Endoósea
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